IBEX: All blocks briefly disconnecting and reconnecting

At 14:46 on 29/03/2020 on MUSR the GUI kept showing all of the blocks in the config as disconnected and then momentarily showed their values, and kept flickering between both states.

This happened on a config load (OXF13_UDR4_high) in the built client after editing a config (OXF13_UDR3_high) and saving it as OXF13_UDR4_HIGH. Switching config (to OXF14_UDR4_high) did not solve this, neither did restarting the blockserver, and the only way to fix the problem was to close and reopen the GUI client. Before this the instrument scientist did switch configs fairly frequently in a short space of time.

We may be able to reproduce this with a squish test or something automated that switches config very frequently and/or uses the "save as" button several times however there was nothing in the logs to indicate what was going on.